کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5418992 | 1506979 | 2006 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Quantum-chemical calculations of the methylation of hydroxamic and thiohydroxamic acids with diazomethane
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موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
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چکیده انگلیسی
We made calculations about the methylation of both hydroxamic and thiohydroxamic acids with CH2N2. The potential-energy surfaces of several proposed pathways leading to possible site-selective products (N-methylated and O-methylated hydroximates) are presented. Our results agree satisfactorily with an experimental observation by Liguori et al. who found site selectivity in the formation of dimethylated products. Simultaneous deprotonation and methylation occurs in both forms (E and Z) of hydroxamic acid and thiohydroxamic acid, and the net energy barrier via this pathway is the smallest. In most corresponding processes the energy barriers are smaller for thiohydroxamic acid, and the Z-form has an energy barrier smaller than that of the E-form in both hydroxamic and thiohydroxamic acids.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure: THEOCHEM - Volume 778, Issues 1â3, 11 December 2006, Pages 27-34
Journal: Journal of Molecular Structure: THEOCHEM - Volume 778, Issues 1â3, 11 December 2006, Pages 27-34
نویسندگان
Chung-Yu Yang, Hui-Lung Chen, Jia-Jen Ho,